Flaw in engines caused October explosion

Earlier this week we finally learned what cause NASA's Antares rocket explosion on October 28, 2014. It turns that when Orbital Science Corp. built the rocket they used old Soviet-built rocket engines that NASA had in storage for the last 50 years.

The engines had a "fundamental flaw in the materials," said a top manager for NASA's contracted rocket builder, Orbital Sciences, in a 2013 interview with an agency historian. The Soviet engines were built in the 1960s and 1970s in a failed attempt to take cosmonauts to the moon.

According to an article written by Melody Pettersen of the Los Angeles Times, government documents show that NASA had known for years that there was a potential flaw in the engines. The documents show that in 2008 a NASA committee issued a warning that these engines hold a “substantial” risk if used. The warning goes on to talk about the cracks that might have developed that could lead to fuel leaks that can cause a catastrophic failure at launch.

“They were never designed to be in storage that long,” said the Orbital manager, Ken Eberly, deputy director for the rocket program.

The explosion, on that October day ten weeks ago, destroyed millions of dollars in supplies headed to the ISS (international spacestation), the rocket and launch pad. The revelation that NASA knew of this flaw raises some questions about their oversight committee.

Why did NASA allow the use of these engines? The answer might be that a press release by Orbital Science Corp. speaks of a successful test after refurbishing the engines. Even with the success of this test there was still reason for concern when a subsequent x-ray showed that the refurbishing wasn't as solid as first thought and could still be a great risk to the mission.

In November the investigation into the explosion first started to focus on the engines. This prompted the CEO of Orbital Science to admitted that a fatal flaw inside the engines could have been the cause.

"While still preliminary and subject to change, the current evidence strongly suggests that one of the two AJ26 main engines that powered Antares' first stage failed about 15 seconds after ignition," Orbital president and CEODavid Thompson said during a conference call today. "At this time, we believe the failure likely originated in, or directly affected, the turbopump machinery of this engine, but I want to stress that more analysis will be required to confirm that this finding is correct." He later added, "We will likely discontinue the use of the AJ26 rocket engines that had been used on the first five Antares launch vehicles unless and until those engines can be conclusively shown to be flightworthy,"